Thanks!

Thank you so much for the good comments! I think it will be difficult to upload within a year due to compulsory service in the South Korean military. I'm sorry. I'll try my best when I'm discharged from the military. I hope you have the knowledge you want by now.

The mbed OS is an RTOS-based platform for ARM Cortex-M series microcontrollers, and the Arduino Pro Mini uses AVR-based microcontrollers. I understand that since these two platforms have different hardware architectures, it is difficult to port the code as it is. If I'm wrong and you've been successful compiling and uploading my code to you, the likely issues may be as follows. - Make sure to check the pin configuration of the Arduino Pro Mini and modify the code accordingly to match the correct pins. There are a few pins for implementing I2C communication on all boards. - Make sure that the AD0 pin on the MPU9250 is low (GND) or high. The MPU9250 has different I2C addresses to access depending on the status of AD0. If the AD0 pin is connected to GND, the I2C address of the MPU9250 is 0x68, and if it's connected to VCC, the address is 0x69 - Try to replace the SCL and SDA pins on the board. It is often confusing when dealing with I2C for the first time. -------------- There may be more various causes, but it is difficult to guess based on the information you gave me. I need information on how far it was successful, how the pins were connected, what modifications were made to the code, etc. Before that, if you use Arduino, I don't think you have to use mbed code. For Arduino, there are simpler and more efficient libraries available for using the MPU9250. Modules that use I2C communication, like MPU9250, have a register called WHOAMI. This register allows you to verify that you are in normal communication with that module. I suggest that you first operate the MPU9250 module and read this register to check if you receive the correct value. . . . Um... If this is a question that the flutter app cannot read the information received from serial communication, you need to check the serial communication settings. - Baudrate: 115200 - Check how it goes, especially if the last byte of the data is a new line character (LF, ASCII code 10) and it is processed as one message. Other than that, I've only tested this flutter program on Linux or Mac. I'm not sure what Windows would be like. Alternatively, when using the Flutter app, try shutting down another IDE (such as the arduino ide). Serial ports cannot be accessed by multiple clients at the same time, so if one application monopolizes the port, another program cannot access it